In recent years, attention has been paid to a recessed source/drain type MOSFET in which a source/drain-region trench (hereinafter referred to as a recess) is formed and a semiconductor layer having a lattice constant different from that of a semiconductor substrate is epitaxially grown in the recess, in order to improve the current driving capability of the MOSFET.
When the recessed source/drain type MOSFET is formed, dry etching is performed to form the recess in the semiconductor substrate and a Chemical Vapor Deposition (CVD) method is used for the epitaxial growth of the semiconductor layer. In addition, Japanese Patent Laid-Open Nos. 08-153688, 2007-305730 and 2007-250837, for example, propose performing treatments to remove contaminants and oxides present on a surface of the recess using a predetermined gas, after the formation of the recess by dry etching and before the epitaxial growth of the semiconductor layer.